Adapter for miniature tubes



Nov. 10, 1953 F. D. M!RABELLA ADAPTER FOR MINIATURE TUBES Filed Aug. 7, 1952 Patented Nov. 10, 1953 UNITED STATES PATENT OFFICE ADAPTER FOR MINIATURE TUBES Frank D. Mirabella, Staten Island, N. Y.

Application August 7, 1952, Serial No. 303,071

1 Claim. 1

My present invention relates to a combination electric tube accessory having a plurality of functions, and consequent advantages, presently to be mentioned, and is primarily intended for miniature vacuum tubes, altho having functions making it desirable for other uses.

The combination accessory hereinafter described and claimed, and shown in the accompanying drawings, functions as a device for retracing inicrophonic noises in tubes, thereby not only improving their electrical performance, but lengthening the life thereof, and also as a cushdevice or shock absorber to preserve tubes against shocks, as in army or other mobile equipment. It further acts to align misaligned tube prongs, and as a tube base, and still further as a socket-tube registration device, thus having a five-fold function, and it has been an object of the invention to provide the simplest and there fore the most economical tube accessory useful in the several mentioned ways.

As to the last-mentioned usefulness, in which the accessory device acts as a socket-tube registration device, this enables multi-pronged electric tubes to be quickly and properly placed in their respective sockets, thus avoiding the loss of time andl patience previously experienced in trying to perform that operation; which, as Well known, is troublesome under the best conditions and more so under less advantageous conditions, as for example when tubes are to be replaced in compact crowded sets Within cabinets.

In the making of electric tubes, it sometimes happens that the bottoms of the tubes are sealed thereto oblique to the main or longitudinal axes thereof, instead of at right angles thereto. As these bottoms carry the sealed-in prongs of the tubes, improper sealing of the mentioned bottoms throws all the prongs out of proper position, the latter position being parallelism with the longi tudinal gas of the tubes. This condition prevents the proper placement or functioning of the tubes in their sockets and at least presents the appearance of defective tubes and must be corrected. The device of the present invention, by encircling or embracing all the prongs, enables an operator to quickly put them all simultaneously into their proper positions, and this alignment is performed without requiring an added operation, being done at the same time as the required placement of the device on the prongs for functioning as a socket-tube registration device or socket-tube coordinator.

My device being preferably made, at least in part, of a soft or semi-soft, low-loss resilient plastic or other suitable material, acts as a cushioning means to prevent undue jarring and con sequent injury to the tubes equipped therewith, which hazard exists for example in traveling or mobile electronic equipment. This feature of my invention is important in that it eliminates the necessity of the practice which has long existed and now exists in the armed services and otherwise, of processing all tubes for the purpose of selecting only the most rugged for conditions subjecting them to considerable vibration, it being known that processes of manufacture inevitably produce some tubes in which the internal elements are less rigidly held than in others. This selective process is known in the art as ruggedizing and it is also known that only about 10% of tubes meet the test for rugged tubes.

The new device also function as a base for miniature tubes, which frequently are not provided with a regular plastic or metallic base, and is simpler and more economical than such bases. In this connection it is to be mentioned that the device, embracing the tube prongs rather tightly, as it does, needs no cementing to hold it attached to the tubes. It is also to be said here that, as a base, the device not only naturally positions itself properly on normal tubes, i. e., at right angles to the longitudinal axes thereof, but also on abnormal tubes wherein, as aforesaid, the bottoms of the tubes are sealed in oblique to the mentioned axes; in such cases, the device also forms a properly positioned base.

One form of the device and its relation to a tube and socket is illustrated in the accompanying drawings, in which Figure 1 is a View showing a miniature radio tube, mostly in elevation but partly in section, said tube carrying my novel accessory device and both fitted into a socket shown partly in section and partly in elevation;

Figure 2 shows the tube and socket of Figure 1 separated, the tube carrying the accessory device:

Figure 3 is a bottom plan of the tube with the accessory fitted thereon, or in other words the bottom plan view of the upper part of Figure 2;

Figure 4 is a plan view of the socket;

Figure 5 is a bottom view of the accessory device showing the guide pin;

Figure 6 is a plan of the device;

Figure 7 is an elevational view, partly in section, of the accessory; the section being central and on the line 'l-'! of Figure 6; and

Figure 8 is an elevational view of the device in the process of being applied to the prongs of the tube, the tube being shown fragmentarily.

Referring to the drawings for a more detailed description thereof, the numeral ll) indicates a miniature radio tube, having no separate base. The prongs 12, connected to elements within the tube, are sealed into the glass bottom of the envelope of the tube and extend below the same. These prongs, as clearly shown in Figure 3, are arranged in a circle, but are not uniformly spaced therein, there being a wider space between the two socalled end prongs, according to practice, so that the prongs may fit only into their proper individual sockets. These sockets, designated by the numeral M, are spaced to correspond to the spacing of the mentioned prongs and are collectively embedded in a body of insulating material and extend below the same and terminate in wire-connecting terminals 15a; It will be noted that a cenral vertical aperture I"! is provided in the insulating body 45, for the purpose her-inafter mentioned, and that this aperture is lined with a metal tube 18 which extends below said body it. It will also be noted that said aperture and tube extend thru a boss 2! which rises above the surface of said body 15. The latter body held within the lower end of a shell 23, as clearly shown in Figures 1 and 2, the elements shown in the lower part of the latter figure being collectively the tube socket The intentionally simple accessory device of the invention, having the several functions previously mentioned, is shown in all the figures, with the exception of Figure and is shown separately or by itself in Figures 5, 6 and '1. This device 21 is preferably made of insulating material, and iesirably of a soft or semi-soft and low-loss plastic material which is resilient, altho the guide pin, presently to be mentioned, may be a conductor. Said device is shown as comprising circular disk 23 from the center of one face of which extends a gui .e pin 20 at right angles to the Said pin is desirably made integral with the disk and longer than the prongs I? of the tube. The mentioned disk is provided with apertures iii of a preferably to somewhat tightly nt over and grip the prongs [2 of the tube, a little pressure being desirably necessary to push the portion of the device into con tact with the bottom of the tube :0. Figure 8 shows the device in process oi being put into place and "1e upper part of Figure 2 clearly shows in position relative to the tube. In this process pin is used to assist in putting the disk into place, and the disk itself serves not only to hold the pin to the tube but to reduce the mentioned inicrophonic noises and to act as a shock; absorber, whereby to secure better electrical performance and lengthen the life of the tube. With the accessory device aiiixed to the tube, the prongs of the latter may be quickly positioned properly and then pushed into their re spective sockets. This is accomplished by putting the pin 29 of the accessory device into the central aperture ll of the socket and turnin the tube thru an arc until the prongs find their proper position and fall into their sockets, it being then only necessary to push on the tube to press the prongs all the way into their sockets, Which are as shown and as usual, oi the spring grip type. As to the other functions r rich the new device performs, these will readily be appreciated from the explanations given above.

While I have herein illustrated and describes. one form of my invention, modifications thereof may be made without departing i'r ll]. the invention itself, and it is to be understood that these come within the invention. For example, one or more of certain of the functions mentioned might be dispensed with. Also, the mentioned guide pin might be hollow might be shorter than the tube prongs, to fit over the mentioned boss 2i which might be formed into a thin pin, over which the modified hollow pin of the device could fit. And while the device has been shown as applied to radio or vacuum tubes, it may also be used on electric plugs, etc.

What I claim is:

The combination with a miniature radio tube having multiple prongs nonsynimetrically projecting from the bottom thereof, of a socket for said tube, and a one-piece adapter of the character described, comprising a synthetic resinous material of low electric loss formed to provide a disk having apertures corresponding in number to the prongs of said tube, said prongs extending thru said apertures with a rather snug fit, said disk thereby functioning to align said prongs and as a base for said tube, said adapter further comprising a pin extending centrally and normally from one face of said disk and having a length greater than the length of said prongs and fitting into a central opening in said socket, said adapter being soft enough so that it functions as a cushioning device or shock absorber and to reduce rnicrophonic noises in the tube, whereby to improve the electrical performance and the life of the tube.

FRANK D. MIRAB- LA.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,192,260 Thor-son Mar. 1940 2281,7355 Wright May 5, 1942 2,524,939 Stephan Oct. 10, 1950 2,529,502 Kelly Nov. ll, 1W0

FOREIGN PATENTS Number Country Date 653,310 Great Britain July 18, 1951 

